Field of the Invention
The present invention relates to a grille shutter device configured to control running air flowing into an engine room through a grille opening located at the front side of a vehicle.
Related Art
As the above type of technique, there is conventionally known a grille shutter device disclosed in Japanese patent application publication No. 2007-1503 (JP-A-2007-1503), for example. This device includes an openable shutter mechanism placed in a grille opening located at the front side of a vehicle, a drive unit for driving the shutter mechanism to open/close, and a control unit for controlling the drive unit according to an operating state of the engine. The control unit controls the shutter mechanism via the drive unit to control running air flowing into an engine room through a grille opening.
Herein, for example, the shutter mechanism is closed during high-speed running of a vehicle to reduce a flow of running air (running airflow) into the engine room, so that the aerodynamic performance of the vehicle can be enhanced. Further, the shutter mechanism is closed during engine starting to reduce the quantity of air to be introduced into a radiator and the running airflow into the engine room, so that the time needed for engine warm-up can be shortened. While the engine temperature is trending higher, the shutter mechanism is opened to increase the quantity of running air flowing into the engine room, thereby enabling cooling the engine to an appropriate temperature.